Draw-press for sheet metal.



PATENTED NOV. 28, 1905.

LL. KELLY.

' DRAW PRESS EoE SHEET METAL.

APPLIUATION FILED MAR.24, 1904.

2 SHEETS-SHEET 1.

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PATBNTED NOV. 28, 1905. LY.

HEBT METAL No. 805,967. I v

' J. L. KELV DRAW PRESS FOR s APPLICATION FI LED INVENTOR dd lhafig mdea-Airway NA J ,i/. I

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UNITED STATES PATENT OFFICE f JOHN L. KELLY, ST. PAUL, MINNESOTA.

' DRAW-PRE SS FOR SHEET METAL. I

Specification of Letters Patent.

Patented Nov. as, 1905.

Application filed Marcl124, 1904. Serial No. 199,759. i

To all whom it may concern:

Be it" known that 1, JOHN L. KELLY, a citizen of the United States,residing at St. Paul, in the county of Ramsey and State of Minnesota,have invented certain new and useful Im: provements in Draw-Presses forSheet Metal, ofwhich the following is a specification.

This invention relates to punching-machines of that type which aredesigned for shaping hollow-and tubular metallic articles, and'theinvention has special reference to a machine of this characterpossessing speclal utlhty as a shaping-machine for seamless caps,crowns, and analogous articles employed in dental work. v 1

To this end the invention primarily contemplates a punching-machinedesigned par ticularly for manufacturing with facility and accuracytelescopic caps or cups employed in the dental bridgeworkcovered by myformer patent, No. 709,410, dated September 6,1902,

while at the same time possessing general utility for making-seamlessarticles of various kinds.

With these and many other objects in View, which will more readilyappear as the nature of the invention is better understood, the

same consists in the novel construction, comshowing the form oftelescopic caps which the machine is particularly designed to make.

Like numerals designate corresponding parts in the several figures ofthe drawings. In carrying out the invention any suitable type of base orstand 1 is employed, and upon this base is mounted a centralsupporting-post 2. This post 2 has a threaded lower end 2 screwed into acorresponding threaded socket 2 in the base, whereby it is fixed to saidbase,

and it also has a boss 2, disposed above the base 1. Arranged on thepost 2 is a horizontal die bed or plate 3, and also arranged on the postis a horizontal plate 4, having a circular series of apertures 17 of acommon diameter for guiding interchangeable reciprocatingplunger-punches 5, of which but one is shown. The plate 4 is also shownas provided with an inner circular series of apertures 16. Theseapertures 16, however,- have nothing to do with my invention, beingmerely provided to render the plate lighter.

The reciprocating plunger-punch 5 is of a size corresponding to the sizeof the cap, tube, or crown to. be shapedand is designed tohave anysuitable detachable connection with the sliding punch-head 6, working inthe upright bearing-box 7, formed at the outer end of the.horizontally-swinging carrier-arm 8, which is formed at the end oppositethe bearing-box 7 with an upright cylindrical bearing-sleeve 9, turningupon the post 2 and held thereon by a fastening-nut or equivalent device10. The sliding punch-head 6 is threaded to accommo date the threadedfeed-spindle 11, having a stem portion 12 projecting through the cap 13at the top of the box, and to the upper end of which is fastened thehand-wheel 14.

- The lower horizontal die bed or plate 3 is 30' of'circular form andprovided at or near the periphery thereof with a continuous seriesofsizing-holes 15 of regularly diminish'ed size. Each of these holes 15 islarger than the next smaller opening in the proportion of the thick- 5ness of the material of which caps are to beformed, so that a capfinally shaped in one of such openings will have an accurate register-,ing or telescopic fit within a cap finally shaped in the next largeropening. The'openings 17 9 in plate 4 correspond in size to the shank ofthe punch 5 and are designed 'to'receive and then operated downward tocarry the disk through such hole to give the same its first I 0 shaping,which will be of a saucer form. The blank in this shape is then placedover the'next smaller sizing-hole 15, anda punch smaller than that firstmentioned is placed in the head 6 and moved down upon the work andthrough 1 5 said hole, thereby giving it the final shape. The sametreatment is carried out in connection with the cap which is totelescope with the one just made, except that the final treatment isnecessarily given in a different-sized I1 sizing-hole 15. The arm 8 maybe freely swung around over the guide-plate'4 to permit of the operationdescribed, and'it will also be obvious that any analogous articles, suchas a dental crown, can be shaped through the medium of theinstrumentalities described.

Various changes in the form, proportion, and minor details ofconstruction may be resorted to without departing from the spirit of theinvention or sacrificing any of the advantages thereof.

It is desired to call attention, however, to the circumference of thepunches and holes, the construction of which makes it possible toproduce sixteen tubes or caps adapted to telescope one within the otherin regular sequence from the smallest to the largest.

It will be gathered from the foregoing that a separate punch must beused for each size of hole in the die-plate 3; but all of the puncheshave shanks of the same diameten-to fit the holes in the guide-plate 4:,which are all of uniform diameter.

Having thus described the invention, what is claimed as new, and desiredto be secured by Letters Patent, is-

1. In a machine of the class described, the combination of a punch, anda die-plate formed with holes uniformly varying in diameter; thedifference in size between each hole and the next larger holecorresponding to the thickness of the metal to be punched, wherebyaccurate telescoping of the tubes formed is assured.

2. In a machine of the class described, the combination of a punch, anda die-plate having a series of holes gradually increased in size inregular sequence; the difierence in size between each hole and the nextlarger hole corresponding to the thickness of the metal to be punched,whereby accurate telescoping of the series of tubes formed in the seriesof 0 threaded punch-head movable vertically in said bearing-box, a punchcarried by said head, a feed-screw engaging the punch-head and having astem extending through the upper end of the bearing-box, and a handdevice mounted on said stem and disposed above the bearing-box.

4. In a machine of the class described, the combination of a die-platehaving a circular series of holes, a post disposed in the center of saidcircular series of holes, a horizontallyswinging arm mounted on saidcentral post and having an upright bearing-box disposed above the seriesof holes in the die-plate, a threaded punch-head movable vertically insaid bearing-box, a punch carried by said head, a feed-screw engagingthe punch-head and having a stem extending through the upper end of thebearing-box, a hand device mounted on said stem and disposed above thebearing-box, and a guide-plate disposed above the die-plate and havingone or more holes alined with a hole or holes of said die-plate.

In testimony whereof I afiix my signature in presence of two witnesses.

JOHN L. KELLY.

Witnesses:

F. T. MGNAMARA, T. PETERSON.

